1. Field of the Disclosure
The present disclosure relates to a backlight unit and a liquid crystal display having the same, and more particularly, to a backlight unit which may facilitate control of output light through a light guide plate, improve light concentration effect, and reduce moire, a liquid crystal display device having the same, and a fabrication method of the backlight unit.
2. Discussion of the Related Art
In general, liquid crystal display devices (LCDs) have been widely used due to advantages thereof, such as low-power consumption, thin profile, excellent quality, etc. A liquid crystal display device includes two substrates disposed opposite each other and a liquid crystal panel consisting of liquid crystals interposed between the two substrates. The liquid crystal panel displays an image by varying liquid crystal arrangement using an electric field generated around the liquid crystals.
Such a liquid crystal panel, which is a non-emissive display panel, requires a light supply device, such as a backlight unit, to display an image and, in general, in the liquid crystal display device, the liquid crystal panel and the BLU are combined together. Backlight units are divided into edge type backlight unit and bottom type backlight unit according to light source positions.
A backlight unit includes a light guide plate and different kinds of optical sheets so as to effectively transmit light supplied to a light source to the liquid crystal panel.
Recently, as the thickness of the liquid crystal display device has been reduced, a product, which has a small number of thin optical sheets and light guide plate and exhibits equivalent or improved effect has been developed.
Therefore, edge type backlight unit has been widely used, as compared to bottom type backlight unit, and a smaller number of optical sheets and a thin light guide plate tend to be used.
Thus, in a modern backlight unit and liquid crystal display device including the same, patterns are formed on the upper and lower surfaces of a light guide plate and serve to compensate for reduction in the number of optical sheets. However, as to a light guide plate with a patterned lower surface, light concentration effect is low and thus, it may be difficult to control output light.
Particularly, in the liquid crystal display device of the related art, moire is generated by the pattern formed on the upper or lower surface of the light guide plate, the pattern of the optical sheet, and the pattern of the liquid crystal display device, such as a black matrix.